Institution: | 1.Department of Mathematics (naXys), 61 Rue de Bruxelles, 5000, Namur, Belgium ;2.Department of Physics, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece ;3.Research Center for Astronomy and Applied Mathematics, Academy of Athens, 11527, Athens, Greece ;4.Department of Mathematics, University of Padova, Via Trieste 63, 35121, Padova, Italy ; |